SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7db17eceedab236beec43e5860bd5618b2ee51b3bf099f19bd833dcea8b2909b' 
  AND token = '9Q59+sZmJX3UGpU/IRQzchBeg7ScuN0IjomUFAVQNOc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}